Salts of pyridoxine mono-esters

ABSTRACT

Pyridoxine mono-esters salts, possessing psychostimulant properties and having the general formula:   IN WHICH: A and A1 represent each an alkylene radical with a chain of up to 16 carton atoms or an amino-hydrocarbon residue, for example an amino-alkylene residue such as IN WHICH R represents a hydrogen atom or a CH3CO group, P BEING 1 OR 2 R1 and R2 either represent each an alkyl radical containing up to five carbon atoms, said radicals being separated or forming with the nitrogen atom a heterocyclic ring. Ac represents a pharmaceutically acceptable acid N IS AN INTEGER TAKING THE VALUE 1,2 OR

United States Patent 1 Esanu [54] SALTS OF PYRIDOXINE MONO- ESTERS [76] Inventor: Andre Esanu, 119 Rue de la Croix- Nivert, 75-Paris, France [22] Filed: Jan. 13, 1971 ,211 App]. No.1 106,245

[30] Foreign Application Priority Data Jan. 21, 1970 Great Britain ..2889/70 [52] US. Cl. .260/268 H, 260/295.5 R, 260/2955 V, 260/297.5, 260/295 R, 424/263, 424/250 [51] Int. Cl. ..C07d 31/34 [58] Field of Search.....260/295 R, 295 VB, 295.5 V, 260/2975 [56] References Cited UNITED STATES PATENTS 3,557,131 1/1971 Yoshimura et a] ..260/295.5 R

Primary Examiner-John D. Randolph Assistant ExaminerRobert T. Bond AttorneyArnold Robinson [5 7] ABSTRACT Pyridoxine mono-esters salts, possessing psychostimulant properties and having the general formula:

[ 1 Feb. 20, 1973 CHQOH O 0 R2 4 II II H0 1 -GHz-O-C-A- -OA1--N R1 HzC 1 N Act,

in which:

A and A represent each an alkylene radical with a chain of up to 16 carton atoms or an aminohydrocarbon residue, for example an amino-alkylene residue such as 1 Claim, No Drawings SALTS OF PYRIDOXINE MONO-TESTERS This invention relates to pyridoxine mono-esters salts, and provides a new class of compounds having in which:

A and A represent each an alkylene radical with a chain of up to 16 carbon atoms or an aminohydrocarbon residue, for example an amino-alkylene residue such as in which:

R represents a hydrogen atom or a CH CO group, p being 1 or 2 R and R either represent each an alkyl radical containing up to five carbon atoms, said radicals being separated or forming with the nitrogen atom a heterocyclic ring. Ac represents a pharmaceutically acceptable acid n is an integer taking the value 1, 2 or 3 The salts of the esters according to this invention have therapeutic activity and may be prepared according to this invention by reacting pyridoxine which has its 3- and 4- positions OH and CH OH groups blocked-with a compound having the general formula C1COA-OOA -NR,R, in which the symbols are as above defined, followed by the liberation of the blocking of OI-I and -CH OI-I groups at the 3- and 4- positions of the pyridoxine ring. The esters thus obtained are then treated by a pharmaceutically acceptable acid to get an acceptable salt. The reaction sequence is illustrated below by way of example a. Blocking of two alcohol functions of pyridoxine 4 OH HO 3 5-CHQOH HUI The resulting compound I is obtained in the form of its hydrochloride and is treated with Na,co, to obtain the free base. The choice of acetone is not critical any usual blocking agent might be used alternatively.

b. Treatment of the compound obtained in a by the appropriate chloride acid The hereinabove chloride may be obtained by the reaction of the anhydride of the corresponding acid with the substituted amino alkanol, to form the substituted amino alkanol mono-ester according to the reaction scheme and this mono-ester, treated with SOCI gives the chloride:

ClCOA--COOA,--NR,R

c. Liberation of OH and CH OH in 3- and 4- positions by treating compound (II) with an acid, to form a compound according to the invention omorr no -or-oo-Ao0oA1-Nmm H20 1,;

I/ DIMETHYLAMINO ETHANOL AND 5,-0: PYRIDOXINE SUCCINATE ture was allowed to rise to room temperatureand the stirring was maintained for a further hour. The mixture was then cooled to 15C and the corresponding 3,4-

isopropylidene pyridoxine was obtained in the form of its hydrochloride (100 g). The free base was obtained by treatment with a solution of Na CO 82 g of base (compound A) were obtained melting at 1 l 1C.

b. Preparation and reaction of the chloride of dimethyl-amino ethanol mono-succinate 100 g of succinic anhydride, 100 g of dimethylamino ethanol and 100 ml of anhydridous acetone were placed into a two liter flask and were there refluxed for 3 hours. The solution was then concentrated to one third of its original volume by evaporation and cooled. A precipitate appeared, which was separated and recrystallized from acetone.

140 g of product were obtained, with a melting point of 78C.

The chloride was prepared from this compound by treatment of 420 g of the compound with freshly distilled SOC] (1.85 liter. After elimination of nonreacted SOCl the product obtained was treated by benzene and dried, to yield 620 g of the hydrochloride of the chloride acid. 120 g of the compound of step (a) above (0.57 mole) were dissolved in 0.5 liter of pyridine. After cooling there were slowly added at about C, during 90 minutes, 170 g (0.69 mole) of the hydrochloride previously obtained, dissolved in 0.2 liter of chloroform. The solution was stirred for hours, then evaporated to dryness (350 g). The residue was dissolved in 0.3 liter of water and was neutralized by an aqueous solution of NH saturated by K CO There was obtained an oily substance which was extracted with chloroform. The extract was concentrated to dryness (170 g).

c. Liberation of OH and CH OH in 3- and 4-.positions by treating compound (II) with an acid, to form a compound according to the invention in this step the blocking group linking the OH in position 3 to the CH OH in position 4 of the pyridoxine ring was broken by hydrolysis with formic acid. 52 g of the product of step (b) above were treated with 1.650 liter of 1 percent solution of formic acid and 0.250 liter of ethyl alcohol. The mixture was boiled for 30 minutes, evaporated again treated with ethyl alcohol and evaporated. Therewere obtained 37 of an oily substance having the formula d. Salts formation 1. Maleate Maleate was obtained by reacting 37 g(0 .l mole) of the above product of step (c) dissolved in 120 ml of acetone with 27 g (0.230 mole) of maleic acid dissolved in 130 ml of acetone.

Melting point 134C The furmarate was prepared by an exactly analogous process.

2. N-acetyl aspartate The N-acetyl aspartate was obtained in an analogous manner to the preparation of the maleate by reacting 22 g (0.64 mole) of the substance of step (0) dissolved in 0.1 liter of ethyl alcohol with 22.4 g of N-acetyl aspartic acid (1.28 mole) dissolved in 0.3 liter of ethyl alcohol. The compound was very hygroscopic Yield 31.5 g

ll/DIMETHYLAMINO ETHANOL AND 5- aPYRlDOXlNE GLUTARATE Step (a) is identical to step (a) of example (I).

In step (b), glutaric anhy'dride is used instead of succinic anhydride.

Step (0) is similar to step (c) of example (I). There is thus obtained an oily substance which is treated by maleic acid as in step (d) of example (I). There is obtained an ochre-white crystalline product melting at l00102C.

Ill/ N-METHYL N-ETHANOL PIPERAZINE AND 5- a PYRIDCXINE SUCCINATE cam Hz a.

an ITO-(f doHroco-cnrcm-coooaz-cHz-N N-CHa (3-0. a \N/ 1&2 Iii;

Step d The compound of step (c) is transformed into a salt by the maleic acid (as in example I step (1). With 3 molecules of maleic acid there is obtained the corresponding tri-maleate, a white product with a bitter and salted taste, melting at about 142C.

These compounds have interesting psycho-stimulant properties as exemplified by Dimethylamino ethanol and S-a pyridoxine succinate maleate. The compound shows at doses from 10 mg/kg, per os, an antagonist action against the hypothermic and ptosic action of reserpine. Moreover a very favorable action has been noticed on the dysfunctioning of the memory in rat and a high rate activity has been noticed on the cortex of the cat with doses of a level of 25 mg/kg I.V.

These compounds present also a low toxicity (in the case of the above mentioned compound it is LD 50 on mice, 1.55 gllcg per 05 or 1.0 g/lcg 1.1

In human therapy, very good results have been obtained on patients suffering from psychastenia, neurotonic depressing syndrome, subjective cranial traumatic syndrome by a treatment comprising the administration, per diem, of 4 to 6 gelatin capsules containing each 0.250 g of the same compound. In all the cases of administration the tolerance has been perfect.

I claim:

1. A salt of a pyridoxine mono-ester having the following formula:

UNITED STATES I PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 717 .636 Dated February 20, 1973 Inventor(s) Andre Esanu It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 6, line 4, represents should read--Al represents (3H 2 Signed and sealed this 9th day of July 1971;

( SEAL) Attest:

MCCOY M. GIBSON, JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents USCOMM-DC 60376-P69 FORM P0-105O (10-69) v us, GOVERNMENT vnm'rms omcs: 19w o-ass-au i i UNITED STATES PATENT OFFICE 7 CERTIFICATE OF CORRECTION Patent No- 3 ,717 ,636 Dated February 20, 1973 Inventoz-(s) Andre ES anu It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

' insert:

On the' cover sheet before Assignee Societe d'Etudes de Produits Chimiques Is sy-Les -Moul ineaux France- Signed-and seeled this 5th day of March 197).;

(SEAL) Attestt EDWARD M.FLETCHER,JR. C, MARSHALL DANN Attesting Officer Commissioner of Patents .ORM PO-105O (10-69) UscoMMDcieovhWg U,$. GOVERNMENT PRINTING OFFICE I969 0-356-334 

